Japan mobile carriers agree on roaming capabilities

At a government panel meeting on Wednesday, the major mobile carriers of TOKYO agreed that they need to introduce roaming capabilities so that their customers can use rival networks during service disruptions.

A Communications ministry panel of experts will discuss the issue with a view to implement the proposal around 2025, with carriers warming to the idea after a recent widespread outage affecting one of them.

In early July, KDDI Corp. suffered a network outage that lasted over 60 hours, affecting 30.91 million people, with users unable to make emergency calls for an extended period.

While NTT Docomo Inc.Docomo Inc. SoftBank Corp. SoftBank Corp. and Rakuten Mobile Inc. agreed on the need for a framework for mobile support in emergencies, there was disagreement on what form it should take.

There are points of contention about whether the function should be limited to using emergency service numbers like 119 or widened to standard calls and whether it will come at a cost to users.

While KDDI and Rakuten Mobile maintained that standard voice communications should be part of the roaming service, Docomo expressed concern that it would place the onus on the network that is receiving an influx of users to provide a stable service.

SoftBank cited dual SIM phones as an example of other approaches that should be considered, as it stated that it is realistic to offer roaming only for emergency contact services.

About 60 percent of Japan's emergency calls are now made by mobile phone, according to the meeting.

Reports came from the KDDI disruption of people with emergency health issues not being able to directly contact their local fire station and having to physically go to them, among other life-threatening cases.

KDDI was ordered by the communications ministry in August to do more to prevent another outage on the same scale.